1. Field of the Invention
The present invention relates to the field of micro-electro-mechanical systems (MEMS) devices, and more specifically, to the field of detection and repair of defects that substantially prevent MEMS devices from functioning properly.
2. Discussion of the Prior Art
Micro engineered devices such as micro-electro-mechanical structures (MEMS) are presently being developed for a wide variety of applications in view of the size, cost and reliability advantages provided by these devices. For example, one advantageous MEMS device is a variable capacitor in which the interelectrode spacing between a pair of electrodes is controllably varied in order to selectively vary the capacitance between the electrodes. Typically, a conventional MEMS variable capacitor includes a pair of electrodes, one of which is disposed upon and fixed to the substrate and the other of which is typically carried on a movable actuator or driver. In accordance with MEMS technology, the movable actuator is preferably formed by micromachining the substrate such that very small and very precisely defined actuators can be constructed.
In general, performance of MEMS devices is adversely affected by the presence of various defects, including mechanical defects as well as electrical defects. Indeed, a typical movable actuator or sensor formed by micromachining the substrate is highly sensitive to the presence of different defects on its surface, as well in its volume, including mechanical and ‘short’ and/or ‘open’ electrical defects.
What is needed is to provide a method to efficiently detect and repair all mechanical as well as electrical defects that substantially prevent MEMS devices from functioning properly.